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Distribution patterns of clonal plants in the subnival belt of the Hengduan Mountains,SW China

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Plant Diversity 2020年第5期42卷 386-392页

作者： Yongqian Gao Jinxuan Zheng Xiangqun Lin Fan du Faculty of Forestry Southwest Forestry University300 Bailong RoadKunming650224YunnanPR China Yunnan Forestry Technological College 1 JindianKunming650224YunnanPR China Forest Inventory and Planning Institute of Yunnan Province Kunming650051YunnanChina

Clonal reproduction(i.e.,production of potentially independent offspring by vegetative growth)is thought to provide plants with reproductive ***,studying the evolution of clonal reproduction in local floras is crucial for our understanding of the adaptive mechanisms plants deploy in stressful environments such as alpine *** this study,we characterized clonal plant species in the subnival belt of the Hengduan Mountains(a global biodiversity hotspot with extreme environmental conditions in southwest China),in order to determine the effects of sex system,growth form,and elevational distribution on *** compiled clonality data of angiosperm species belonging to 41 families in the subnival belt of the Hengduan Mountains using published *** the 793 species recorded in the region,47.92%(380 species)are clonal *** sex system and growth form had significant effects on the occurrence of clonal reproduction:unisexual species(79.79%)were more likely to be clonal than bisexual species(43.63%),and herbaceous species(51.04%)were more likely to be clonal than woody species(16.67%).Compared with non-alpine-endemic species(44.60%),alpine-endemic species(58.33%)showed a significantly higher proportion of clonal *** logistic regression analysis showed a positive association between incidence of clonality and elevational range,indicating that species distributed at high elevations are more likely to be ***,the elevational gradients in clonality were contingent on sex system or growth *** study reveals that plants in the subnival belt of the Hengduan Mountains might optimize their probability of reproduction through clonal reproduction,a finding that adds to our growing understanding of plant's adaptations to harsh alpine environments.

关键词： Alpine Clonal reproduction Hengduan mountains Sexual reproduction Subnival belt

B(C_(6)F_(5))_(3)-Catalyzed Hydroboration of Alkenes with N-Heterocyclic Carbene Boranes via B-H Bond Activation

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Chinese Journal of Chemistry 2021年第4期39卷 918-926页

作者： Qiaotian Wang Wei Meng Xiangqing Feng Haifeng du Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing100049 China

Main observation and conclusion In this work,a novel mode for the activation of N-heterocyclic carbene boranes(NHC-boranes)was developed by generating the highly reactive zwitterion species through hydride abstraction with Lewis acid B(C_(6)F_(5))_(3) in an frustrated Lewis pairs manner.A broad range of alkenes including stilbenes,β-methylstyrenes,styrenes,and alkyl-alkenes were suitable substrates for the B(C_(6)F_(5))_(3)-catalyzed hydroboration to furnish the desired products in good to high ***,excellent regioselectivities were obtained in some *** studies indicate that the B-H bond cleavage is likely involved in the rate-determining *** addition,an electrophilic addition of NHC-borenium cation to alkenes and the subsequent formation of carbocation are also *** current work provides a promising method for the activation of stable borane adducts,which might lead to some interesting transformations in the future.

关键词： Frustrated Lewis pairs Hydroboration B-H bond activation Boranes Alkenes

Kinetics for hydrogen production by methanol steam reforming in fluidized bed reactor

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Science Bulletin 2016年第5期61卷 401-405页

作者： Fuxiang Zhang Yingshuang Shi Lijun Yang xiaoze du Key Laboratory of Condition Monitoring and Control for Power Plant Equipment (North China Electric Power University) Ministry of Education

Hydrogen is one of the best energy *** bed reactor provides a promising approach for hydrogen production. To describe the hydrogen generating rate with methanol steam reforming in fluidized bed reactor quantitatively, dual-rate kinetic models of the reactions with exponent form were developed, including that of steam reforming reaction(SR) and decomposition reaction(DE).The reaction rate per unit mass of catalyst was related to partial pressures of components. The exponentials in kinetic equations were obtained by linear least-squares method based on the experimental data. The variance homogeneity test(F test) shows that the dynamic models are feasible with high accuracy, which can be used to predict the generating rate of hydrogen under different reaction temperatures and feed flow rates in fluidized bed reactor. The SR and DE activation energy obtained indicates that ESR\ EDE, which can explain the previous observation that the CO_2 selectivity decreased with the temperature increase.

关键词： Kinetics model Methanol steam reforming Hydrogen production Fluidized bed reactor

A Galaxy Image Augmentation Method Based on Few-shot Learning and Generative Adversarial Networks

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Research in Astronomy and Astrophysics 2024年第3期24卷 180-193页

作者： Yiqi Yao Jinqu Zhang Ping du Shuyu Dong School of Artificial Intelligence South China Normal UniversityFoshan 528225China School of Computer Science South China Normal UniversityGuangzhou 510631China Guangdong Construction Vocational Technology Institute Guangzhou 511500China

Galaxy morphology classifications based on machine learning are a typical technique to handle enormous amounts of astronomical observation data,but the key challenge is how to provide enough training data for the machine learning *** this article proposes an image data augmentation method that combines few-shot learning and generative adversarial *** Galaxy10 DECaLs data set is selected for the experiments with consistency,variance,and augmentation effects being *** popular networks,including AlexNet,VGG,and ResNet,are used as examples to study the effectiveness of different augmentation methods on galaxy morphology *** results show that the proposed method can generate galaxy images and can be used for expanding the classification model’s training *** to comparative studies,the best enhancement effect on model performance is obtained by generating a data set that is 0.5–1 time larger than the original data ***,different augmentation strategies have considerably varied effects on different types of ***-GAN achieved the best classification performance on the ResNet network for In-between Round Smooth Galaxies and Unbarred Loose Spiral Galaxies,with F1 Scores of 89.54%and 63.18%,*** comparison reveals that various data augmentation techniques have varied effects on different categories of galaxy morphology and machine learning ***,the best augmentation strategies for each galaxy category are suggested.

关键词： techniques image processing-galaxies structure-galaxies general

考试焦虑量表在长沙市初中生中的应用结果分析

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中国临床心理学杂志 2008年第2期16卷 146-147,150页

作者：凌晓范晓玲湖南师范大学教育科学学院

目的:研究长沙市初中生的考试焦虑现状,评价中文版TAI在初中生中的适用性。方法:期中考试前两周用TAI对3680名初中生施测,一周后对107名同类学生进行TAS测试和TAI重测。结果:①长沙市初中生在TAI总量表和分量表上的得分大于平均数2个标... 详细信息

目的:研究长沙市初中生的考试焦虑现状,评价中文版TAI在初中生中的适用性。方法:期中考试前两周用TAI对3680名初中生施测,一周后对107名同类学生进行TAS测试和TAI重测。结果:①长沙市初中生在TAI总量表和分量表上的得分大于平均数2个标准差以上的占总人数的5%左右;②初中生的考试焦虑存在显著的性别、年级和学校类型差异;③TAI各条目与总、分量表的相关及总、分量表之间的相关均达到显著水平,重测信度分别为0.86、0.72、0.82,TAI总分与TAS总分之间的相关达0.58。结论:中文版TAI能够应用于长沙市初中生。

关键词： TAI 考试焦虑初中生

Intra-abdominal inflammatory myofibroblastic tumor:Spontaneous regression

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World Journal of Gastroenterology 2014年第37期20卷 13625-13631页

作者： Jun-Jie Zhao Jia-Qian ling Yong Fang xiao-Dong Gao Ping Shu Kun-Tang Shen Jing Qin Yi-Hong Sun Xin-Yu Qin Department of General Surgery Zhong Shan HospitalFudan University

Inflammatory myofibroblastic tumors are usually treated by surgical resection. We herein report two cases of intra-abdominal inflammatory myofibroblastic tumors that were unresectable and underwent spontaneous regression without any treatment. Our case report and literature review show that regression is more common in the middle-aged and older male populations. Abdominal discomfort and fever were the most common symptoms, but the majority of patients had no obvious physical signs. There was no specific indicator for diagnosis. The majority of the lesions regressed within3 mo and nearly all of the masses completely resolved within 1 year. We conclude that the clinical characteristics of inflammatory myofibroblastic tumors are variable and, accordingly, the disease needs to be subdivided and treated on an individual basis. Surgery is always the first-line treatment; however, for those masses assessed as unresectable, conservative therapy with in-tense follow-up should be considered.

关键词： Inflammatory myofibroblastic tumor Inflammatory pseudotumor Abdominal cavity Spontaneous regression

Experimental evolution and proximate mechanisms in biology

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Synthetic and Systems Biotechnology 2017年第4期2卷 253-258页

作者： xiao Yi BioTechnology Institute University of MinnesotaSt.PaulMN 55108USA

Biological functions e studied by molecular,systems and behavioral biology e are referred to as proximate *** and how they have emerged from the course of evolution are referred to as ultimate *** the conceptual and technical schism between the disciplines that focus on each,studies from one side can benefit the *** evolution is an emerging field at the crossroads of functional and evolutionary *** microorganisms and mammalian cell lines evolve in well-controlled laboratory environments over multiple *** changes arising from the process are then characterized in genetics and function to understand the evolutionary *** providing empirical tests to evolutionary questions,such studies also offer opportunities of new insights into proximate *** evolution optimizes biological systems by means of adaptation;the adapted systems with their mutations present unique perturbed states of the systems that generate new and often unexpected output/***,learning about these states not only adds to but also might deepen knowledge on the proximate *** demonstrate this point,five examples in experimental evolution are introduced,and their relevance to functional biology *** some examples,from evolution experiments,updates were made to known proximate processes e gene regulation and cell *** some examples,new contexts were found for known proximate processes e cell division and drug resistance of *** one example,a new cellular mechanism was *** cases identify ways the approach of experimental evolution can be used to ask questions in functional biology.

关键词： Experimental evolution Proximate mechanisms Ultimate mechanisms Gene network Modules

Association of sterol regulatory element binding protein 2 and insulin-like growth factor binding protein 3 genetic polymorphisms with avascular necrosis of the femoral head in the Chinese population

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Chinese Medical Journal 2012年第22期125卷 4037-4043页

作者： SONG Yang du Zhen-wu LI Qiu-ju ZHANG Gui-zhen WANG ling-ling WU Ning WANG Jin-cheng GAO Zhong-li Jilin Univ China Japan Union Hosp Dept Orthoped Changchun 130033 Jilin Peoples R China Jilin Univ China Japan Union Hosp Cent Res Dept Changchun 130033 Jilin Peoples R China

Background Sterol regulatory element binding protein （SREBP）-2 plays a key role in lipid homeostasis by stimulating gene expression of cholesterol biosynthetic pathways. The insulin-like growth factor binding protein （IGFBP） family regulates growth and metabolism, especially bone cell metabolism, and correlates with osteonecrosis. However, association of their gene polymorphisms with risk of avascular necrosis of the femoral head （ANFH） has rarely been reported. We determined whether SREBP-2 and IGFBP-3 gene polymorphisms were associated with increased ANFH risk in the Chinese population. Methods Two single nucleotide polymorphisms of SREBP2 gene, rs2267439 and rs2267443, and one of IGFBP-3 gene, rs2453839, were selected and genotyped in 49 ANFH patients and 42 control individuals by direct sequencing assay. Results The frequencies of rs2267439 TT and rs2267443 GA of SREBP2 and rs2453839 TT and CT of IGFBP-3 in the ANFH group showed increased and decreased tendencies （against normal control group）, respectively. Interaction analysis of genes revealed that the frequency of carrying rs2267439 TT and rs2267443 GA genotypes of SREBF-2 in ANFH patients was significantly higher than in the control group （P 〈0.05）. Association analysis between polymorphisms and clinical phenotype demonstrated that the disease course in ANFH patients with the rs2453839 TT genotype of IGFBP-3 was significantly shorter than that of CT＋CC carriers （P 〈0.01）. CT＋CC genotype frequency in patients with stage Ill/IV bilateral hip lesions was significantly higher than in those with stage Ill/IV unilateral lesions and stage II/111 bilateral lesions （P 〈0.05-0.02）. Conclusions Our results suggested that interaction of SREBP-2 gene polymorphisms and the relationship between the polymorphisms and clinical phenotype of IGFBP-3 were closely related to increased ANFH risk in the Chinese population. The most significant finding was that the CT＋CC genotype carriers of IGFBP-3 rs2453839 were highly associate

关键词： avascular necrosis of femoral head sterol regulatory element binding protein-2 insulin-like growthfactor binding protein 3 gene polymorphism

Delay effect in the Lasota-Wazewska model with multiple time-varying delays

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International Journal of Biomathematics 2018年第1期11卷 301-311页

作者： Songlin xiao Academy of Intelligent Software Guangzhou University Guangdong Provincial EngineeringTechnology Research Center for Mathematical Educational Software Guangzhou 510006 P. R. China

In this paper, the effect of delay on the asymptotic behavior of a Lasota-Wazewska model with multiple time-varying delays is investigated. By employing the fluctuation lemma and some differential inequality techniques, delay-dependent criteria are obtained for the global attractivity of the considered model. An example is also given in the end of this paper to show the effectiveness of our results.

关键词： Lasota Wazewska model global attractivity multiple time-varying delay.